Bow-spring mounting for the slide valves of triple valves



Oct. 10, 1933. c. A. CAMPBELL 1,929,576

BOW SPRING MOUNTING FOR THE- SLIDE VALVES OF TRIPLE VALVES Filed Nov. 30, 1932 6 QM/0341 Q 7 3nventor (I ttornegs Patented Oct. v r J. r v

' Y "UNIrEo /srATEs PATENT OFFICE v f' BOW-SPRING MOUNTING FOR THE SLIDE VALVES TRIPLE VALVES Charles A. Campbell, Water-town, N. Y5, assignor, v

to. They New York Air Brake Company, a corporationv of New'Jersey I "Application November 30, 1932 Serial No. 645,066

' iolaims. (01. 303-33) ,4

"This invention relates to triple valves and interior of the bushing, as will be obvious from particularly to the spring mechanism used for an inspection of Fig. 2 of the drawing. Increase holding the slide valve to its. seat. I of clearance makesgit' possible for the slide valve According to, long established practice, the to lift While decrease causesxitto bind in the 5 slide valve works in a slide valve chamber bushing. Inward deflection of a wing or both 5 formed in a cylindrical brass bushing. A flat wings. causes binding of the graduating valve seat for the slide valve is broached out in one with the wings; These are frequently the cause side of the bushing and serves to confine the of malfunctioning of triple valves. slide valve quite closely to right line movement The present invention provides a'simple conin the direction of the axis: ofjthe cylindrical struction of fulcrum pin which can be quickly bushing. The slide valve likewise is made of inserted and fastened in placewithout danger brass and is provided with upstanding wings or of deforming the wings; and which can -be lugs between which. the graduating. valve is quickly removed without danger of deforming closely confined so that 'it has longitudinal the wings. The pin consists of a tube-through movement in the direction of the axis of the cy-' the bore of which a soft deformable wire is;in- 7i) lindrical bushing. The two valves are. actuated serted. This wireprojects' ateach end and is;

by a piston stem which extends longitudinally bent over into position to engage the outer faces over both valvesfbetween the wings, lost motion of the wings and prevent withdrawal of the tube. relatively to the piston stem'being permitted to The preferred embodiment of the-invention at least one of the valves. The piston stem is will now be described with reference to the ac- 75. guided at one end by the triple piston, and at companyingdrawin in which,

the other end by a spider which works 'in'the Fig.1 is a fragmentary longitudinal axial seccylindrical bushing. tion through the valve chamber bushing of a It is highly important that the slide valve be triple valve, the slide'valve, graduating valve closely confined to, its seat with which it makes and piston stem being shown in elevation, cera lapped fit. If the valve were permitted to rise tain parts being broken away. from its seat particles of grit might enter be- Fig. 2 is a section on the line 2-2 of Fig. 1. tween the valve and its seat and score one or Fig. 3 is a view of the fulcrum pin assembly both. For this reason the wings are extended before insertion, the tubular pinbeing shown in 3Q upward into contact with that side of the cyllongitudinal section. 1 inder bushing opposed to the valve seat, the Referring first to Figs. 1 and 2, 6 represents effect being to confine the valve quite closely to the valve chamber bushing of a triple valve, and its seat without impairing its freedom of motion. 7 represents the triplepiston stem, which is of To exert a definite seating pressure at all ordinary form and which is guided at its inner. times on the valve 9. bow-spring is pivoted on a (right hand) end by. a spider 8 which contacts fulcrum pin which extends transversely through with the interior of the bushingfi and is cutopposed wings. Furthermore, a leaf or other away or fluted at its periphery to permit the free spring is interposed between the stem and the passage of air. The outer or left hand end of graduating valve. In this mechanism, as herethe stem '7 is guided by the triple piston, as will tofore constructed, the fulcrum pin was a brass be well understood by those skilled in the art. 9 rod only slightly longer than the overall width Between the spider 8 and a collar 9 on the cause deformation of the wings, that is, the out a portion of the bushing. In this way the V 0- outward in the operation of driving out a fulthe bushing to contact with the bushing v across the two opposed wings, the rod being re- .stem 7 a slide valve 11 is mounted so as to have tained by riveting over its ends. The operation lost motion'relatively to the stem 7. This slide of riveting the. ends has been found likely to valve works on a seat 12 formed by broaching wings are forced toward each other. Furthervalve 11 is confined laterally by shoulders 13 more, even if the wings are not distorted in the formed in the bushing. Along its lateral edges initial insertion of the pin, they are almost the slide valve is provided with parallel flanges certain to be damaged by being bent inward or or wings 14 which project across-the interior of crum pin, when for any reason this becomes as indicated at 15. The upper edges of the wings necessary. Deformation of the wings is harmful are machined to conform to the interior circular for two reasons. It increases or decreases, accontour'of the bushing. cording to the direction of displacement, the .Closely confined between the wings 14 is the 5 5 clearance between the top of the wings and the graduating valve 16 which works on a seat 1'7 1.

formed on the back of the slide valve 11. The valve 16 is held in a notch 18 formed in the stem 7 and is urged against the seat 1'? by a leaf spring 19. A tubular fulcrum pin 21 extends through opposed wings 1 L and'carries the'usual bow-spring 22 which-contacts at its ends with the interior surface of the bushing. The pin 21 is retained by a deformable wire 23 which is inserted longitudinally through the bore of the pin 21. It projects at each end from the tubular pin and is bent laterally" so as to preclude withdrawal of the pin by engagement of the ends of the wire with the wings 14. -The bent portions are indicated at 24.

In making up the pin assembly the parts are arranged as shown in Fig. 3. The wire 23 is inserted through the bore of the pin 21. One end is bent at right angles, as indicated at 24 in Fig. 3. The other end is bent laterally slightly, as indicated at 25 in Fig. 3, the bend being sufiicient to preventwithdrawal of the wire, and insufficient to prevent insertion of the tubular pin 21. As a rule the Wire 23 is made of soft bronze or copper. The wire may readily be bent into retaining position or may be bent up to free the fulcrum pin without danger of bending bore of said tubular fulcrum pin, and having its end portions bent'laterally to retain said pin by engagement with said wings. I

2. The combination with a valve chamber bushing having a slide valve seat; a slide valve shiftable on said seat and having spaced wings projecting from its back andv adapted to coact with said bushing to prevent substantial separation of said valve from its seat; a tubular fulcrum pin extending through said wings; a bowspring tiltably mounted on said pin and coacting with said bushing to hold said slide valve against said seat; and a readily deformable wire extending through the bore of said tubular fulcrum pin, and having its end portions bent laterally to retain said pin by. engagement with said wings.

3. The combination with a valve chamber bushing having a slide valve seat; a slide valve shiftable on said seat and having spaced wings projecting from its back and adapted to coact with said bushing to prevent substantial separation of said valve from its seat; a graduating valve slidable on the back of said slide valve between said wings, said graduating valve being guided in its motion relatively to the slide valve by said wings; a tubular fulcrum pin extending through said wings; a bow-spring tiltably mounted on said pin and coacting with said bushing to hold said slide valve against said seat; a readily deformable wireextending through the bore of said tubular fulcrum pin, and having its end portions bent laterally to retain said pinby engagement with saidwings; a shiftable stem guided in said bushing, engaging said graduating valve to shiftvthe same and having lost motion engagement with said slide valve to shift the slide valve; and a'spring reacting between said stem and graduating valve to hold the graduating valve seated on theslide valve. U

4. A fulcrum pin assembly for bow-springs of triple slide valves, comprising in combination, a a tubular pin; and a deformable wire inserted through the bore of and projecting beyond the ends of said pin, the projecting ends of said wire being bent laterally sufficiently to retain the wire in the pin, and at least one such bent end being so formed as to permit insertion of the end of the pin through a closely fitting aperture.

CHARLES A. CAMPBELL. 

